The Aquatic Realm: Insights into the Development Status of the Aquaculture Industry

1. Why Choose the Aquaculture Industry?​

With the continuous development of society, against the backdrop of increasing market demand and a sharp decline in marine fishing, aquaculture is the most viable solution for supplying aquatic products. It is an environmentally responsible alternative that can provide high – quality, fresh, nutritious, safe, and affordable aquatic products.​

Fishery is the last major food source still relying on “hunting – like activities” for large – scale supply. This supply method is gradually declining and is no longer suitable for today’s society. Thus, the aquaculture industry has risen rapidly and now shoulders the responsibility of supplying more than half of the aquatic products.​

2. Classification of Aquaculture Systems​

Aquaculture systems can be open-type (ponds), semi-intensive (cages), or intensive (Recirculating Aquaculture Systems – RAS). This classification depends on the number of organisms cultured per unit volume of water and the relationship between water source and water supply. Traditional pond culture is open-type; cage culture is semi-intensive, but it is intensive inside the cage; and the Recirculating Aquaculture System (RAS) is an intensive system.

Ponds and cages are open-type systems, so pollution from the air and water sources is inevitable. As a result, water quality control in pond and cage systems becomes more difficult, and the growth efficiency of the organisms cultured in them is relatively limited. Although the water environment principles of the Recirculating Aquaculture System can be applied in open-type systems, there is no control over the environment.

Comparison between Traditional and Recirculating Aquaculture Systems (RAS)​

Traditional aquaculture methods, such as outdoor pond systems and net-pen systems, are not sustainable in the long run due to environmental constraints and the inability to ensure product safety. In contrast, RAS can achieve sustainability, unlimited expansion, environmental friendliness, and quality control.

1. Characteristics of Traditional Aquaculture Systems​

• Disadvantages of Traditional Aquaculture Systems

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Serial Number	Disadvantages
1	Requires a large amount of space;
2	Limited natural available sites;
3	Environmental problems caused by fish excrement;
4	Geographical limitations due to weather and climate;
5	Vulnerability to diseases, predators, and natural disasters caused by uncontrollable outdoor environments.

The environment of traditional aquaculture systems has a natural disadvantage in dealing with disease infections, and the result may be a complete loss. In the system, fish diseases can spread rapidly through direct cont

• The environment of traditional aquaculture systems has a natural disadvantage in dealing with disease infections, and the result may be a complete loss. In the system, fish diseases can spread rapidly through direct contact with infected organisms. If the system uses drinking water sources for breeding, the possibility of disease infection is low unless diseased fish or carriers are introduced. Even if a disease occurs, effective water quality management measures make the treatment more effective than in traditional outdoor systems.

• Outdoor pond and net – pen systems also have the disadvantage of being unable to continuously supply aquatic products because they cannot control the growth cycle, resulting in fixed peaks and valleys in the market availability of aquatic products. In addition, the escape of cultured animals, especially genetically modified varieties, is a major problem. At this time, RAS is the only viable technology because cultured animals in an indoor environment will neither escape nor affect natural populations.​

2. Characteristics of Recirculating Aquaculture Systems (RAS)​

• The government’s agricultural construction plan strongly promotes the development of facility – based fisheries such as factory-scale recirculating aquaculture.​

• The aquaculture system can be expanded infinitely (without geographical or environmental restrictions).​

• It has obvious advantages in aquaculture environment control (easier to resist external risks and can maintain the optimal growth state of cultured organisms throughout the year).​

• Saves water and land and is pollution-free.​

• No drugs are used throughout the aquaculture process.​

• Enables high-density aquaculture.​

• The advantage of indoor RAS is that it allows aquaculture in a controllable environment, enabling the control of growth rates and harvest cycles. RAS achieves the reuse of water through the filtration of biological filters, reducing heat loss and water consumption. RAS has a high – efficiency agglomeration effect, achieving the best yield per unit area and per unit of labor among all models. RAS is environmentally sustainable because it requires 90% – 99% less water than traditional methods, occupies less than 1% of the land, and its waste treatment is also environmentally friendly.​

• Indoor aquaculture is likely the only way to ensure 100% food safety, without chemical and heavy – metal residues. With the increasing attention of consumers to food safety, RAS practitioners face unprecedented opportunities. Fresher and safer local aquatic products are a significant advantage of RAS. Since RAS can be designed to harvest fish weekly, it is no longer limited by the environmental risks and seasonal harvests of pond culture, thus gaining more initiative.​

3. Summary​

Against the backdrop of continuously increasing market demand in today’s society, aquaculture has addressed the shortage of aquatic product supply. It is an environmentally responsible alternative that can provide high – quality, fresh, nutritious, safe, and affordable aquatic products. Factory-scale recirculating aquaculture, as an emerging aquaculture method that can effectively ensure food safety, has undergone extensive verification and commercial applications over the past 40 years and has achieved remarkable development. Each subsystem process has become more refined.d, making the factory – scale recirculating aquaculture model highly attractive.​

4. Case Sharing​

Case: A Grouper Aquaculture Base in Wuhan​

• Project Name: A Grouper Aquaculture Base in Wuhan​

• Cultured Species: Marine Groupers​

• Scale and Output: Currently, the aquaculture water volume is 2000 m³​

• Cooperation Content: This project is an inland artificial seawater grouper aquaculture. By using the MCT technology of [the company], with nitrifying bacteria, biofilm-forming agents, and biological carriers for bacteria cultivation, a biological system was successfully established. The ammonia-nitrogen removal efficiency of the biological MBBR carrier is >200 g/(m³·d), and the nitrite removal efficiency is >180 g/(m³·d), completely replacing the original packing materials.